1348 has been established which involves lyophobic and electrostatic binding. The ester in the resulting complex has been shown to undergo an “intramicellar” displacement, the rate of which is dependent upon the mole fraction of AT as A’,,+. The maximum first-order rate constants for ester disappearance (-0.06 to 0.2 min-I)
are comparable to those for the poorer substrates of esteratic enzymes. We believe our initial endeavors in this new field show sufficient promise to pursue the Acknowledgments. This work was supported by a grant from the National Institutes of Health.
Communications to the Editor Synthesis by the Merrifield Method of a Protected Nonapeptide Amide with the Amino Acid Sequence of Oxytocin’ Sir: Since the synthesis of oxytocin was first accomplished ~ other syntheses have by du Vigneaud, et U I . , several been all utilizing the same nonapeptide intermediate as was used in the original synthesis but, in some cases, with different protecting groups. With all of these approaches, in which the classical methods of peptide chemistry are employed, many weeks and, in some cases, months are required for the synthesis of the required protected nonapeptide amide intermediate and the over-all yields are low. Using the method of solid-phase peptide synthesis recently introduced by Merrifield, a protected nonapeptide has been synthesized in high yield in a few days. Removal of the protecting groups followed by oxidation and purification yielded oxytocin. The protected nonapeptide was synthesized in a stepwise manner beginning with 6 g of t-butyloxycarbonylglycyl resin containing 1.236 minoles of glycine according to the general procedure of Merrifield,l3,l4 with the following modifications. (1) Chloroform was used as a solvent for the triethylamine neutralization steps and for the washes immediately preceding and following these steps.’j (2) Trifluoroacetic acid was (1) Supported by grants from the Medical Research Council of Canada and the Quebec Medical Research Council. (2) V. du Vigneaud, C. Ressler, J. M. Swan, C. W. Roberts, P. G. Katsoyannis, and S. Gordon, J . Am. Chem. Soc., 75, 4879 (1953); V. du Vigneaud, C. Ressler, J. M. Swan, C. W. Roberts, and P. G. Katsoyannis, ibid., 76, 3115 (1954). (3) R. A. Boissonnas, S. Guttmann, P. A . Jaquenoud, and J. P. Watter, Xelo. Chim. Acta, 38, 1491 (1955). (4) J. Rudinger, J. Honzl, and M. Zaoral, Collection Czech. Chem. Commun., 21,202 (1956). ( 5 ) L. Velluz, G. Amiard, J. Bartos, B. Goffinet, and R. Heymes, Bull. Soc. Chim. France, 1464 (1956). (6) C. H . Beyernian, J. S . Bontekoe, and A. C. Koch, Rec. Trau. Chim., 78, 935 (1959). (7) (a) M. Bodanszky and V. du Vigneaud, J . Am. Chem. Soc., 81, 2504 (1959); (b) ibid., 81, 5688 (1959). (8) L. Kisfaludy, S. Dualsky, S. Bajusz, M. Low, A. Uskert, and I
